Selective zone sand control completion



R. W. DONALDSON ETAL SELECTIVE ZONE SAND CONTROL COMPLETION Filed March 28, 1963 May 24, 1966 ROBERT W. DONALDSON JOE 8. JUSTUS FIG.1

producing zones at 9400 ft., 9600 ft. and 9800 ft.

United States Patent 3,252,515 SELECTIVE ZGNE SAND CONTROL COMPLETEUN Robert W. Donaldson, New Orleans, La., and Joe B. Justus, Fullerton, Califl, assignors to Chevron Research Company, a corporation of Delaware Filed Mar. 28, 1963, Ser. No. 268,820 Claims. (Cl. 166-114) The present invention relates to oil production and, more particularly, the present invention relates to sand control completion of at least a pair of spaced apart producing zones penetrated by a well.

In the oil producing art it is not uncommon for one well to penetrate more than one producing zone. For ex ample, a 10,000 foot well might penetrate petroleum It is often desirable to produce all of the Zones simultaneously. However, it is sometimes desirable to alternate production from the zones. A well must be completed for selective production it it is desired to alternately produce from the zones.

A further problem that is often associated with oil production from multizone producing strata is the tendency of the producing formation to produce sand with the produced oil. This is particularly true in some areas of the Gulf Coast, for example. Many methods of sand control have been tried to prevent producing sand with the produced oil. One of the most successful methods includes the use of prepacked sand control liners. A prepacked sand control liner comprises a porous sand filtering section having an interior slotted liner through which the oil may be produced. Heretofore it has been diflicult to complete a producing well penetrating at least a pair of spaced apart producing 'zones for sand control when it was desired to selectively produce petroleum from the zones.

It is a particular object of the present invention to provide apparatus for selective sand control completion of at least a pair of spaced apart producing zones penetrated by a well, which apparatus is adapted to selectively allow production from either of the zones alone or from both the zones simultaneously through a single conduit leading to the surface.

In a broad aspect, the present invention provides apparatus for sand control completion of at least a pair of spaced apart oil producing zones penetrated by a well. In accordance with the invention a first pack-01f means is positioned in a well between a pair of producing zones to pack off the well between the zones. A second packofl means is positioned in the well above the upper of the producing zones. Chamber means are provided in the well between the first pack-off means and the second packofi? means. A single conduit, which forms the only fluid flow path through said second pack-01f means, is provided in fluid communication with said chamber means for flowing petroleum therefrom through the second pack-off means and then to the surface. Sand control means, including a porous sand filtering section having an interior slotted liner are positioned in the well between the first and second pack-off means and adjacent the upper producing zone. A first tubular member communicates with the slotted liner of the sand control means and opens into said chamber means to form a path for fluid flow from said upper producing zone through said sand control means to said chamber means. Retaining means are formed in the upper portion of the first tubular member for disconnectably connecting plug means in the first tubular member to selectively control fluid flow from the upper producing zone through said first tubular member. A second tubular member is provided in fluid communication with the chamber means. The second tubular member extends through said first pack-off means to form a flow path for fluids from the lower of said producing zones into the chamber means. Retaining means are formed in the upper portion of the second tubular member for disconnectably connecting plug means in the second tubular member to selectively control fluid flow through the second tubular member. The second tubular member is provided with slotted means below the first pack-off means to permit fluidsfrom the lower producing zone to flow into the second tubular member. Plug means are provided with extendible dogs for cooperation with the retaining means of said tubular members for disconn'ectable connection in the tubular members to selectively control fluid flow through the tubular members. Thus petroleum production through the sand control completed well can be from the lower zone alone through a single conduit, or from the upper zone alone through the same conduit, or from both zones simultaneously through the same conduit.

Further objects and advantages of the present invention will become apparent from the following detailed description read in light of the accompanying drawing which is made a part of this specification and in which:

FIG. 1 is a view partly in section of a well illustrating a preferred embodiment of apparatus assembled according to the present invention and arranged for production from the lower of a pair of producing zones;

FIG. 2 is a View partly in section of a well illustrating the preferred embodiment of apparatus assembled according to the present invention and arranged for production from the upper of the pair of producing zones;

FIG. 3 is a view partly in section of a well illustrating the preferred embodiment of apparatus assembled according' to the present invention and arranged for simultaneous production from the pair of producing zones.

With reference to the drawing, and to FIG. 1 in particular, a well casing 10 is shown casing a well which penetrates an upper producing zone 12 and a lower producing zone 14. The well casing 10 has appropriately placed perforations indicated by the numerals 16 and 18 through which fluid from the producing zones 12 and 14 flows into the interior of well casing 10. The present invention may be practiced in an uncased well; however it is generally preferred to case all wells in present oil well practice.

In accordance with the present invention a first packolf means 20 is provided to pack off the well casing 10 between the pair of producing zones 12 and 14. A second pack-off means 22 is positioned to pack off the well casing 10 above the upper 12 of the producing zones. A string of production tubing 28 is the only path for fluid flow up the well through the second pack-oil means 22. Chamber means 26, having a generally larger crosssectional area than the production tubing 28, is formed in the well casing between the first pack-off means 20 and the second packoff means 22. A single conduit, for example the production tubing 28, extends through the second pack-off means 22 and is connected with chamber 26 by suitable means such as collar 30 to form the only fluid flow path through the second pack-off means 22. The production tubing provides a path for fluid fiow from the chamber means 26 through the pack-off means 22 to the surface.

The upper 12 of the producing zones is completed in a suitable manner for sand control. For example, sand control means, including a porous sand filtering section 32 having an interior slotted liner 34, are positioned in the well casing 10 adjacent the slots 16 in the casing. Fluid flow from the producing zone 12 occurs through the porous sand filtering section 32 and into the interior of the slotted liner 34. One form of sand control means suitable for use in the present invention is illustrated and described in US. Patent 3,039,535 issued June 19, 1962. A first tubular member as which is in fluid communication with the interior of chamber means 26 is provided with a suitable connection with the slotted liner 34. For example, the threads 38 matable with the threads provided on the slotted liner 34 serve to connect the parts and to thus form a path for fluid flow from the upper producing zone 12 into chamber means 26.

A second tubular member 40 which is also in fluid communication with chamber means 26 is connected by suitable means to a conduit 41 and it extends to the first pack-off means 20. A locator sub 42 and an extension tube 45 are connected with conduit 41 and provide a flow path for fluids from the lower 14 of the producing zones into chamber means 26. The extension tube means 45 is provided with means such as slot means 42 which permit fluids from the lower producing zone 14 to flow into the second tubular member 40. The extension tube means 45 may extend into a conventional sand control prepack (not shown). The flow path thus formed extends in an uninterrupted manner past the upper sand control means 32 to the chamber means 26.

Retaining means such as, for example, an annularly extending locking groove 44 are formed in the first tubular member 36. Retaining means, such as the annularly extending locking groove 46, are formed in the second tubular member 40. The retaining means are formed in the upper portion of the tubular members. Locking plug means, such as plug means 48 shown in FIG. 1, are provided with fluid-tight seals 50 and are disconnectably connectable in the retaining means to prevent fluid flow through a selected tubular member. The locking plug means are provided with extendible and retractable dogs 52 which cooperate with annular groove 44 to disconnectably connect the plug means 48 in the first tubular member 36. An annularly extending flange 54 is provided on the upper end of locking plug means 48 for conventional wire line insertion and removal of the plug means 48 from retaining means 44. When the apparatus is assembled as shown in FIG. 1 production from the well occurs only from the lower 14 of the producing zones. The operator of the well may initially position the locking plug means 48 in tubular member 36 When the apparatus is run in the well or alternatively the plug means 48 may be inserted and removed from the tubular member from the surface by well-known wire line methods.

FIG. 2 illustrates an arrangement of apparatus in accordance with the present invention wherein the locking plug means 60 is disconnectably connected in tubular member 48 by the action of extendible and retractable dogs 62 disconnectably engaged in annular groove 46.

' The locking plug means 48 has been removed from the upper portion of tubular member 36 and thus the well is producing only from the upper 12 of the producing zones. In this respect it is pointed out that the insertion and removal of the locking plug means can be accomplished by well-known wire line methods. For example a kick-over tool is used to position and remove the locking plug means in the tubular member which is eccentric with the production tubing. Conventional wire line methods can be used to place and remove the locking plug means in the tubular member which is approximately concentric with the production tubing. The locking plug means may be of any suitable configuration to selectively prevent and allow flow through a articular tubular member.

FIG. 3 illustrates an arrangement of apparatus in accordance with the present invention where both the plug means have been removed from the tubular members 36 and 40 and thus production of the well occurs from both the upper 12 and the lower 14 producing zones through the upper pack-01f means 20 by means of a single conduit 28. Sand control means comprising a porous sand filtering section 51 and slotted interior liner 42 are positioned adjacent the lower 14 of the pair of producing zones. In this manner both of the producing zones are completed for sand control. In accordance with the present invention then production may be maintained free of undesirable sand from either the lower or the upper zone alone or from both zones simultaneously. Further, the zones may be alternatively produced by selectively inserting and removing the plug means.

A procedure for setting up a well for selective completion in accordance with this invention is outlined below. This procedure is not intended to limit the invention but is intended rather as a guide in helping one skilled in the art to practice the invention. After a well has been drilled and cased to a desired level, for example, to penetrate a pair of producing zones, the casing adjacent the lower of the zones is perforated in a suitable manner. A lower pack-off means, and a prepacked sand control liner if desired, are run and set by conventional wire line or tubing methods. The casing adjacent the upper zone is then perforated by suitable means such as a gun perforator. Then, usually on the surface, a lower zone locator sub with an extension tube is connected with a tubular member. The tubular member extends through a dual zone prepack and is connected to a chamber means. Another tubular member is connected to the interior slotted liner of the dual zone prepack and to the chamber means. If desired locking plug means may be placed in one, or both, of the tubular members prior to running the apparatus in the well to control fluid flow from the production zones. A conduit is extended from the chamber means and through an upper pack-01f means. This assemblage of apparatus is then run into the well on production tubing and the extension tube is inserted through the lower packoif means. The upper pack-off means is set in a conventional manner and the well may be selectively produced.

It is apparent that modifications other than those described herein may be made to the apparatus of this invention without departing from the invention concept. It is intended that the invention embrace all equivalents within the scope of the appended claims.

We claim:

1. Apparatus for selective sand control completion of a pair of spaced apart oil producing zones penetrated by a well comprising first pack-off means in a well between a pair of producing zones, second pack-off means in said Well above the upper of said producing zones, said second pack-otf means being the only pack-off means in said well above the upper of said producing zones, chamber means in said well between said firstpack-off means and said second pack-oil means, a single conduit extending through said second pack-off means to form the only fluid flow path therethrough and communicating with said chamber means for fluid flow therefrom through said second pack-ofli means, sand control means including a porous sand filtering section having an interior slotted liner positioned in said well adjacent said upper producing zone, a first tubular member communicating with said slotted liner and opening into said chamber means to form the only path for fluid flow from said upper producing zone through said sand control means to said chamber means, retaining means formed in the upper portion of said first tubular member for disconnectably connecting plug means in said first tubular member to selectively control fluid flow through said first tubular member, a second tubular member opening into said chamber means and extending through said first pack otf means to form the only flow path for fluids from the lower of said producing zones to said chamber means, retaining means formed in the upper portion of said second tubular member for disconnectably connecting plug means in said second tubular member to selectively control fluid flow through said second tubular member, and slot means in said second tubular member below said first pack-oil means permitting fluids from said lower producing zone to flow into said second tubular member.

2. The apparatus of claim 1 further characterized by plug means disconnectably connected in one of the said retaining means.

3. The apparatus of claim 1 further characterized by a porous sand filtering section formed around the slot means in the second tubular member.

4. The apparatus of claim 1 further characterized in that the retaining means are-annularly extending grooves formed in the interior walls of the tubular members.

5. Apparatus for selective sand control completion of a pair of spaced apart oil producing zones penetrated by a well comprising first pack-off means in a well between a pair of producing zones, chamber means in said well above said first pack-off means, a conduit connected to said chamber means for fluid communication therewith, said conduit extending up said well as the only flow path from said chamber means to the surface, second pack-off means between said conduit and the well wall, said second pack-off means being the only pack-off means in said well above the upper of said producing zones, sand control means including a porous sand filtering section having an interior slotted liner positioned in said well adjacent the upper of said producing zones, a first tubular member communicating with said slotted liner and opening into said chamber means to form the only path for fluid flow from said upper producing zone through said sand control means to said chamber means, retaining means formed in said first tubular member for disconnectably connecting plug means in said first tubular member to selectively control fluid flow through said first tubular member, a second tubular member opening into said chamber means and extending through said first pack-oft means to form the only flow path for fluids from the lower of said producing zones to said chamber means and retaining means formed in the said second tubular member for disconnectably connecting plug means in said second tubular member to selectively control fluid flow through said second tubular member.

References Cited by the Examiner UNITED STATES PATENTS 2/1961 Daffin et a1. l66-224 6/l962 Hathorn et al. 166228 

5. APPARATUS FOR SELECTIVE SAND CONTROL COMPLETION OF A PAIR OF SPACED APART OIL PRODUCING ZONES PENETRATED BY A WELL COMPRISING A FIRST PACK-OFF MEANS IN A WELL BETWEEN A PAIR OF PRODUCING ZONES, CHAMBER MEANS IN SAID WELL ABOVE SAID FIRST PACK-OFF MEANS, A CONDUIT CONNECTED TO SAID CHAMBER MEANS FOR FLUID COMMUNICATION THEREWITH, SAID CONDUIT EXTENDING UP SAID WELL AS THE ONLY FLOW PATH FROM SAID CHAMBER MEANS TO THE SURFACE, SECOND PACK-OFF MEANS BETWEEN SAID CONDUIT AND THE WELL WALL, SAID SECOND PACK-OFF MEANS BEING THE ONLY PACK-OFF MEANS IN SAID WELL ABOVE THE UPPER OF SAID PRODUCING ZONES, SAND CONTROL MEANS INCLUDING A POROUS SAND FILTERING SECTION HAVING AN INTERIOR SLOTTED LINER POSITIONED IN SAID WELL ADJACENT THE UPPER OF SAID PRODUCING ZONES, A FIRST TUBULAR MEMBER COMMUNICATING WITH SAID SLOTTED LINER AND OPENING INTO SAID CHAMBER MEANS TO FORM THE ONLY PATH FOR FLUID FLOW FROM SAID UPPER PRODUCING ZONE THROUGH SAID SAND CONTROL MEANS TO SAID CHAMBER MEANS, RETAINING MEANS FORMED IN SAID FIRST TUBULAR MEMBER FOR DISCONNECTABLY CONNECTING PLUG MEANS IN SAID FIRST TUBULAR MEMBER TO SELECTIVELY CONTROL FLUID FLOW THROUGH SAID FIRST TUBULAR MEMBER, A SECOND TUBULAR MEMBER OPENING INTO SAID CHAMBER MEANS AND EXTENDING THROUGH SAID FIRST PACK-OFF MEANS TO FORM THE ONLY FLOW PATH FOR FLUIDS FROM THE LOWER OF SAID PRODUCING ZONES TO SAID CHAMBER MEANS AND RETAINING MEANS FORMED IN THE SAID SECOND TUBULAR MEMBER FOR DISCONNECTABLY CONNECTING PLUG MEANS IN SAID SECOND TUBULAR MEMBER TO SELECTIVELY CONTROL FLUID FLOW THROUGH SAID SECOND TUBULAR MEMBER. 